Extragalactic Astronomy - Fall 2012
Homework #2 - due August 29



1. Is M31 (the Andromeda galaxy) within or outside of the zone of avoidance.  You may want to use the Coordinate Converter tool available under the Tools tab on the HEASARC web site.

2. A Cepheid has a period of 31 days, a visual (V band) magnitude of 19.4, and a reddening E(V-B) = 0.1.   Is the star in the Milky Way?

3. Which classes of supernovae are thought to be explosions of massive stars and which are thought to be explosions of white dwarfs?

4. How does the mass in gas in the Milky Way compare with the mass in stars?

5. How does the metallicity of young stars compare with that of old stars?  Explain.

6. What measurement allows us to identify Sgr A* as the dynamical center of the Milky Way?

7. Should part of the grade in this class be based on your "quality of failure"?